The primary objective of this project is to investigate potential substrates of permanent, remote memory and to determine the mechanisms involved in the formation of these stable memories. By using the Pavlovian fear conditioning paradigm, we will be able to further examine retrograde amnesia and consolidation processes across the electrical, molecular, and systems levels. In specific aim 1, the amount of distal damage produced by excitotoxic lesions of the hippocampus, and the effect of this damage on retrograde amnesia and remote memory, will be determined. In specific aim 2, the neuroanatomical substrates involved in permanent memory will be explored by lesioning multiple neocortical areas; thus further illuminating the nature of remote, stable memories. Lastly, specific aim 3 will examine and compare the fundamental phenomenology and basic mechanisms of post-training and post-reactivation amnesias, in the hope of determining whether the same, or dissociable, processes are involved in both consolidation and reconsolidation. Taken together, the present studies will provide a preliminary framework within which to further our understanding of permanent memory, retrograde amnesia and consolidation processes.